DIY Home Improvement Forum banner

Need to build stairs--Is there a Stair Kit?

22K views 13 replies 10 participants last post by  Cocoxoxo 
#1 ·
I want to build 8 deck stairs/ 4 feet wide and I could use some advice. I'm looking for an easy way to build stairs- preferably a stair kit. I don't have a lot of time or a big budget for this project. I don't want to hire anyone to do it either. I know I could do all the math and cut all the stringers myself, but it's a hassle for me. I'm concerned about making a mistake and then I'll have to throw out a lot of expensive material. I'm also thinking about redoing my basement stairs. I don't want to use a pre -built stair because I need the flexibility to make changes. Does anyone have any good ideas of a quality stair kits out there for wood stairs? PLEASE let me know, thank you!
 
#7 · (Edited)
Stairs, and how they work.

I’m going to begin by telling you some things even many of us professionals either overlook or do not understand.

Your weight is not supported by the crispness nor by the accuracy of the fancy cuts involved in making a stinger. The only part of a stringer that carries weight is the continuous part remaining BELOW the cuts. That slim, narrow strip of lumber you see running the length of the whole staircase is all that is keeping the full stairway from coming down.

This is one reason all the impatient carpenters who make their stringer cuts completely with a circular saw (not finishing off the cuts cleanly and squarely with a hand saw) are dead wrong in doing so. That extra couple of inches of saw kerf taken from the lower portion of the stringer weakens it.

In most areas of our country there are no existing building codes for this vitally important part of the stringer. The height of the individual steps (the ‘RISE’) is taken into consideration. The width of the TREAD upon which your foot rests (the ‘RUN’) is also dictated. But not the meat of the stringer that supports all the weight.

In general, it is an accepted practice to assure that at least 5-1/2” of material is left in a stringer after the cuts are made. I personally feel it should be closer to six inches, or more. Code only calls for 5".

Nor do many municipalities stipulate how many stringers to use in constructing an average staircase. Did you know that almost all normal stairways built in the older houses of the past have only two (2) stringers? This is an important fact to absorb. There was a reason for it.

Using more than two stringers sounds good… at first. But it often causes more problems than you might expect. You see, there is very little leeway for any error or discrepancies in the dimensions of each stringer used in a set of stairs.

A single stair tread will sit comfortably on just two stringers even if they are not cut ‘exactly’ identical. Add a center stringer and everything changes. If that center stringer is cut even a sixteenth of an inch higher or larger across the space where a given tread will sit, that tread will have a tendency to ‘rock’ on the center stringer. It will not rest equally on all three stringers unless they are all three perfectly identical in every measurement and angle. This seldom happens. Erroneous measurements, slightly different cuts, the natural ‘crowning’ of different pieces of lumber used… all contribute to the likelihood that those three stringers will not turn out to be identical to one another.

Even if you COULD guarantee that all the stringers were perfect matches, you have yet another couple of problems to deal with. The installation of the stringers where they rest on the floor and against the upper framing members has to also be perfectly aligned. Again, this doesn’t often happen in the real world. Secondly, if there is any bowing of the tread lumber, it cannot sit flatly on three or more stringers.

So, on a normal three or four foot wide stairwell, two stringers are better than three unless the center stringer has been cut a little smaller than the two side stringers, and adjusted with glued shims to tighten the fit to the treads. This is one more thing that usually is not done.

In most good stair work, the treads are made of sufficiently thick material to carry the weight of a person across the stairway span. This is usually all you need… It’s really tough to break a 2” thick board only three feet long.

Surprisingly, a part of the stair structure that helps to support your weight upon the tread is the riser. But only if properly installed. Improperly installed, a riser does little more than add extra weight to a stairway. Unfortunately, most carpenters are not cognizant of this. They consider the riser as nothing but a decorative addition to conform to the building codes.

The riser material is going to be from 6” to almost 8” high all the way across the length of the tread. That is a very strong piece of wood by itself… without the tread helping out. It will provide tremendous additional support to the edge of the tread above it right where your foot comes into contact with the tread. But, as I said, only if properly installed.

This effective installation involves little more than routing a dado (a groove) in the lower edge of the riser. This dado encases the full edge of the back of the lower tread in each set of two treads.

It is installed this way: (Follow along with the accompanying drawing)

Install the two stringers.

Place the first riser directly on the floor with the top edge even with the stringer tread cuts for the first step.

Cut the second riser 2-1/2” wider than the intended riser height, and cut a dado into it that will soon receive the back edge of tread #1. (This assumes 2" treads.... for simplicity)

Now install the riser for the second step. It nails right into the face of the stringers with the dado groove facing outward.

Put a bead of glue in the dado groove and on top of the stringer tread cuts

Slide the tread for the first step into the dado groove on riser #2.

Nail through riser #2 into the tread from the back (the inside of the stairwell)

Now nail the tread down to the stringer. (Yes, you could have nailed the tread down first if you chose to. This sequence really doesn’t matter much.)

The first step is now installed. You simply repeat this installation sequence all the way up.
 

Attachments

#2 ·
You seem to have an idea that you do not commit to any concept. It doesn't work that way. A staircase needs to conform to a rigid principal of redundancy. Every step needs to be the exact replicar of the one before and the one after. There is no flexibility.
You measure the two finished floor heights. You divide it by a desired rise and you adjust to suit. This is the only flex you have.
I would start with the precept of 4 stringers for a 4' wide staircase.
Ron
 
  • Like
Reactions: Cocoxoxo
#3 ·
Ron's right. There are some brackets available that take the stringer cutting out of the equation, but they do not make the layout and math any easier. Cutting them is the easy part. For a 4' wide stair you need AT LEAST three 2x12mstringers, preferably four.

My best advice is to measure your height from landing to landing and do your layout on paper. Actually draw the stringers out. It makes laying them out and cutting them pretty simple. Once you've done the first one you're home free because you can trace it onto the others. Also, get yourself an inexpensive framing square (24" L-shaped device), which is the perfect tool for stair layout.

Pre-cut stringers are a joke, don't waste your time with them. I've never seen a stair making kit that made the job any easier.

www.stairways.org has an informative .pdf that is a visual interpretation of the stair code. That'll help you with getting the rise/run correct.

I say do it the "hard way" and then you'll have accomplished something that you can take some pride in.
 
#4 ·
Many framing squares come with "The Little Blue Book" This book will give you a great guide for stair lay-out. A set of brass stops are a good $5.00 investment to keep your setting accurate.

Some people can not (or are unwilling) figure out the process.That is when a call to a skilled carpenter is the best step.

Inspectors will spot a miss-cut stair right off--bad stairs are flat out dangerous--and the inspectors job is to catch dangerous situations.

Good luck-have fun---Mike---
 
#5 ·
Draw it, check it, measure it twice.

There are online tutorials for calculating and cutting the stringers. The most common mistake is that novices tend to forget to add and subtract for the steps and how it lands at the top. Hiring a carpenter for a few hours is probably better then a kit. And then you will learn how to do it from a guy that knows exactly how to do it, if you pick the right carpenter.
 
#6 · (Edited by Moderator)
Building wood stairs

One of the major issues facing the stair builder is the unpredictable overall stair height that often occurs with basement stairs. The basement slab height nearly always seems to vary up or down, making pre-built stairs problematic. For this reason basement stairs are usually built to customized heights. I wouldn’t recommend pre-built stairs. However, I’ve used an adjustable stair bracket system made by EZ Stairs
(... ). It’s easy to install, and you can build a quality, strong stair that’s ICC-ES approved. I can adjust and tailor my stairs to the exact space allotted. I know it’s a different method than what is described above, but it really has helped me stay in budget and work fast. I use them for deck stairs too. By the way, there’s a stair calculator on the site and it does all the math for you. Good luck.
 
#9 ·
Old School Principles and New Methods

This thread brings out some interesting points about the art of building stairs.
I have spoken to some true craftsmen who are rightfully proud of their ability to cut stringers and build stairs. They are good at it, can do it accurately, quickly and like to build stairs well using traditional methods.

I'm a handyman, not a craftsman and although I have the ability to figure out stair stringers, like Cocoxoxo who started this post, I don't have a lot of time or a big budget. For people like us, the EZ-Stairs system mentioned by Deckman100 is a pretty good way to get the job done. It's a strong accurate stair and much easier to build.
Also, the steel brackets are powder coated so they're OK for deck stairs.

Good luck with your project and thanks for this post. We all got quite an education on stair building.
John aka JayKay
 
#10 ·
Something we used to do in the old days when using thinner tread lumber was to save the triangular cut-outs from making stringers. These were glued and nailed to a 2x 4 or 2x6 in a reverse manner to simulate stringers.

This faked-up stringer was used for a center stringer when you needed to use one on cheaper stairs. (Today, a 2"x36" tread will run you well in excess of $100 each, and a barn or a shed didn't get that kind of luxury lumber.)

It was built by using one of the previously cut stringers as a pattern, building the phony right on top of a regular stringer. Since the 'cut-outs' were smaller due to the wood lost in saw cutting, you set the front edges right along the pattern riser edges.

This always left a small space where the tread crossed the center fake stringer. You shimmed that area with a few glued shims to give extra support to the center of those thinner treads.

Actually, just as strong as measured and cut stringers.
 
#11 ·
Willie makes some quite good points about stair building.
Another note about the depth of material left on a stringer: add another layer to the uncut portion of the stringer. Nail/glue/screw a 2 by 4/6 to the inside bottom of each stringer to stiffen them up.
 
#12 ·
Stair Kit Found!!

:thumbsup:After much decision, I decided to go with the EZ Stairs bracket system in building my deck and basement stairs. I've just heard too many good things about it from all my investigation and I thought it was worth trying. I have to tell you that I'm really impressed. The installation has gone very easily/ smoothly. One thing that was really helpful was being able to adjust my basement stairs because of the uneven flooring. My stairs are strong and they look like a pro built them. They were very cost effective too.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top